Farhad A.

I bought an esp-32 module, with development board, Solar panel controller and LiIoN battery charger module plus a step up DC/DC converter to control the pump of my balcony hydroponic unit.

I need to program the ESP-32 to turn the pump 2-4 times a day to begin with, then move on to add more functions to control and maintain the unit and eventually send messages if there are any need for maintenance.

It's the first embedded controller design I've done since I left work in 2020. I'm very rusty.

The whole package cost about €11. The battery will be one 18650 I salvaged from old laptop battery.

#ESP32 #Solarpanel #DIY #Hydroponic

May 20 at 5:35pmWeb
Show threadcurl | sudo bashMay 20

@faab64

w00t ! 😀

Show threadShdwdrgnMay 20
@faab64 For solar you're going to want to keep power requirements to a minimum. I believe they make something called a "locking" or "latching" relay, in which you set the state and then can remove power. This would ideally let you have the ESP turn on when needed, change the pump state, then go back to sleep. I'm not sure an 18650 has enough juice to keep the ESP running 24/7?
Show threadFarhad A.May 20

@Shdwdrgn
Thanks for the suggestion.

My plan is to put the device in sleep .ode between the activities. I hate 10W solar panel that should be enough to handle the ESP-32 and 3 USB water pumps active 3x10 minutes per day.

Show threadShdwdrgnMay 20
@faab64 Should be interesting! One issue I've had with sleep mode on ESP8266 boards is the timing isn't quite accurate, and can be off by 5-10 seconds even during a 5-minute sleep. It helps if you can query a wifi time service when the device wakes up to keep your pump cycles from drifting through the day.
Show threadFarhad A.May 20

@Shdwdrgn

Interesting, My application is not time accurate. running water pumps 10 minutes, 2-4 times per day, doesn't matter how accurate it is. my main interest is to make a low power, low cost controller for 3 hydroponic units I have on the balcony using solar panels.

I have not checked the power requirements, but I am sure 10W solar is enough with 3x18650 batteries. It will give me at least 40Wh per day.

The pumps are 6W each, they will be active about 3x4x10minuete= 120 minutes per day. so about 12Wh per day. so I have 28Wh left for the ESP-32 and the rest of the electronic.

Show threadShdwdrgnMay 20
@faab64 Nice, that definitely makes things easier if you don't care about the clock! Sounds like you'll have plenty of power to work with, hope you post results as you work through the project.
Show threadFarhad A.May 20
@Shdwdrgn
Thanks. It's going to take me some time to refresh my memory. But I will definitely put updates and make it available to public.